BEHAVIORAL SELECTION BY CONSEQUENCES

Selection as a process consists of (a) variation of traits, (b) differential interaction with the environment on the basis of the variation of traits, and (c) differential replication of beneficial, adaptive traits in the form of their transmission to and expression in future generations of a population. Behavior analysts suggest selection applies to the analysis of an organism’s behavior just as much as to an analysis of its morphology and the origin of species. The three levels at which behavior analysts apply the principle of selection are (a) phylogenic, for the development of an innate repertoire in a species; (b) ontogenic, for the development of an operant repertoire in the lifetime of an individual organism; and (c) cultural, for the development of cultural practices in a social group. Much of traditional psychology is committed to postulating antecedent causes of behavior, particularly where those causes are assumed to be mental. This article argues that a science of behavior is well-served by setting aside concerns with antecedent mental causes in favor of selection by consequences as a causal mode. Key words: B. F. Skinner, behavior analysis, Charles Darwin, evolution, selection by consequences.

BEHAVIOR ANALYSIS AND PRAGMATISM

For pragmatism, the meaning of a psychological concept or statement is found in its practical implications for human affairs. Absent is any assumption that the concept or statement represents the Truth about a metaphysical Reality that lies beyond human experience and behavior. Behavior analysts embrace pragmatism, and argue that an important consideration in psychology is the degree to which a psychological concept or statement contributes to effective action in the laboratory or in service delivery. The effective action commonly takes the form of prediction and control. Keywords: pragmatism, prediction and control, mentalism, levels of analysis, neuroscience

A COMPARISON OF THE EXPLANATORY PRACTICES OF MENTALISM AND BEHAVIOR ANALYSIS

Mentalism is an orientation to the causal explanation of behavior in which the causes are inferred to be unobservable structures from a non-behavioral domain. Typically, the structures are held to underlie behavior, and the domain is that of “mind.” In some but not all cases, mentalism subscribes to traditional psychophysical or substance dualism. Arguments that mental explanations are at the theoretical or conceptual level fail to consider the source of the explanation in question. Behavior analysts oppose mentalism on pragmatic, rather than ontological grounds: mentalism impedes a genuine science of behavior contributing to prediction and control by misleading scientists and inducing them to accept ineffective explanations of their subject matter. Key words: behavior analysis, explanation, mentalism, scientific method, theory, verbal behavior.

PRIVATE BEHAVIORAL EVENTS

Private behavioral events are those events in which the stimulation with respect to which an individual responds is not accessible from the vantage point of another person. In such cases, the stimulation may be verbal or nonverbal. Further, the responses with respect to this stimulation may be verbal or nonverbal, and accessible or not to others. One type of private event involves verbal reports occasioned by conditions of the body, such as aches and pains. A second type involves covert operant behavior, such as thinking, problem solving, and daydreaming. For each type, a naturalistic account may be developed based on concepts derived from the analysis of overt behavior. Key words: B. F. Skinner, private behavioral events, problem of privacy, problem solving, thinking, verbal reports.

METHODOLOGICAL BEHAVIORISM

Early approaches to psychology assumed that mental life was the appropriate subject matter of the new science, and that introspective verbal reports and reaction times were the appropriate methods to support inferences about that subject matter. The problem was that these early approaches were vague, unreliable, and generally ineffective. Methodological behaviorism arose as an attempt to deal with this problem by asserting that theories and explanations in psychology, as well as the concepts they deployed, should be agreed upon. The key to agreement was that psychologists should talk only about observables, although talk of mental unobservables was later permitted if they were designated as theoretical constructs that were operationally defined through their relation to observables. This later view remains prominent in traditional psychology. The radical behaviorism of B. F. Skinner’s behavior analysis offers an alternative based on a critical analysis of the behavioral sources of control over a given term. In particular, the radical behaviorist concept of private behavioral events provides a unified account of nature in behavioral terms. Key words: verbal behavior, methodological behaviorism, radical behaviorism, operationism, prediction and control, private behavioral events, covering law, scientific method

Large Scale Visualization of Pulsed Vortex Generator Jets

The use of small jets of air has proven to be an effective means of flow control on low Reynolds number turbine blades. Pulsing of these jets has also shown benefits in reducing the amount of air needed to achieve the same level of flow control. An experiment using Hot Wire Anemometry and Particle Image Velocimetry (PIV) has been used to investigate how these pulsed jets interact with the boundary layer to help keep the flow attached. A 25x scaled jet in a flat plate has been utilized. The 25.4 mm diameter jet has a pitch angle of 30° and a skew angle of 90°. Pitch angle is defined as the angle the jet makes with the surface of the plate, and the skew angle is the angle that the projection of the jet on the surface makes with the crossflow. The jet was pulsed at both 0.5 Hz and 4 Hz with varying pulse durations (duty cycles), as well as various blowing ratios (ratio of the jet velocity to the freestream velocity). Duty cycles of 10, 25, 50, and100 percent were implemented at a blowing ratio of unity. Blowing ratios of 0.5, 1, 2, and 4 were implemented at a 50% duty cycle and at 0.5 Hz. Velocity and vorticity planes were obtained at various spanwise locations and used in the characterization of the jetflow. Both the free jet as well as the jet in crossflow were studied. A calibration experiment was also performed using PIV on a rotating disk. The calibration experiment was successful and the PIV results averaged a 1.56% error. The hot wire experiment with the free jet showed that the starting vortex is a key event at the beginning of each cycle, and the end of each cycle included a “kick-back” and a suction effect that could also have an influence on the boundary layer. The PIV experiment was performed first on the free jet, and results were comparable to the hot wire results. When the PIV experiment was performed on the jet in crossflow, it was clear that both the beginning and ending events of the jet cycle were keys to eliminating or delaying flow separation.The effect of the beginning and ending events can be used to keep the flow attached for longer periods of time by increasing the frequency of the jet pulse. Due to limitations of the setup, higher frequency cases could not be studied. However, the experiment was successful in controlling a separated crossflow for blowing ratios greater than unity. The larger blowing ratios resulted in larger attachment size, and were able to sustain attachment for longer time periods